Securing coupling for corrugated pipes

ABSTRACT

The coupling includes a tubular sleeve having a circumferential wall and an open end for receiving the corrugated pipe, the tubular sleeve having a sleeve section which is pivotable radially outward from the sleeve by means of an integral hinge connecting the sleeve section to the circumferential wall. A first locking tongue is arranged in a first aperture in the circumferential wall, the first aperture being located in the sleeve section. The first locking tongue is resiliently connected to the sleeve section and has a first blocking projection which is engageable with a circumferential groove in the pipe, the first locking tongue being movable radially outward with resilience to release the blocking projection from the groove. A second locking tongue is arranged in a second aperture in the circumferential wall, the second aperture being located opposite from the first aperture. The second locking tongue is resiliently connected to the sleeve and has a second blocking projection which is engageable with the circumferential groove in the pipe, the second locking tongue having a lever arm which extends toward the open end of the sleeve. The lever arm is movable radially inward to move the second locking tongue radially outward with resilience to release the second blocking projection from the groove.

PRIORITY CLAIM

This is a U.S. national stage of application of PCT/EP00/08045, filed onAug. 17, 2000. Priority is claimed on that application and on thefollowing applications: Country: Germany, Application No: 299 14 435.6,filed Aug. 21, 1999; Country: Germany, Application No: 199 39 149.1,filed Aug. 21, 1999; Country: Germany, Application No: 299 16 743.7,filed Sep. 24, 1999; Country: Germany, Application No. 199 45 751.4,filed Sep. 24, 1999.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention concerns securing couplings for corrugated pipes.

Various types of securing couplings for corrugated pipes have been knownfor many years. Numerous types indicate spring-loaded locking elementswith elastic fingers which are provided with projections which againengage in a wave trough of a corrugated pipe in order to establish andaccomplish a position-fixation of the pipe. The fingers of suchcouplings suffer an elastic deflection when the pipe is pushed into andremoved from its position.

2. Description of the Related Art

DE 39 03 353 discloses a connecting fitting for circumferentiallyflanged pipes or hoses, particularly for flexible corrugated hoses withcorrugations or the like which are transverse to the hose axis and runaround the circumference. The connecting fitting has a sleeve toaccommodate the end of the corrugated hose, and in the wall of thissleeve there is a single tongue, which is deflectable against arestoring force of a resilient region. This tongue extends in the axialdirection of the sleeve and has a projection directed into the interiorof the sleeve for the purpose of engaging a corrugation or the like ofthe corrugated hose or corrugated pipe to fix its axial position. Theregion of the tongue exhibiting the projection has a large dimension inthe circumferential direction and the length of the projection in thecircumferential direction of the sleeve is at least approximately equalto the internal radius of the sleeve.

In DE 296 13 054 U1, a pipe connector made of plastic is disclosed,consisting of a sleeve-shaped body designed to accommodate a rigid orflexible pipe (hose). The jacket of this body contains at least oneformed tongue, which is formed by a somewhat U-shaped recess and hasspring-supported movement around its base. The tongue has at its freeend a blocking element for engaging in a recess or for a rear grip of aflange of a pipe pressed forward into position, and the tongue and theblocking element are oriented at a right angle to the sleeve axis.

EP 0414500 discloses a coupling wherein a finger is connected with thetubular body of the coupling by way of lateral mounting elements whichensure that the finger has flexible or resilient displacement because ofelastic torsional straining of the elements around a transverse axis.

The disadvantage with all these couplings is the fact that the lockingelements or fingers, respectively, are either too weak in order to keepthe corrugated conduit in position against a strong withdrawing force,or they are strong enough to hold the corrugated conduit but are toostiff to allow the conduit to be pressed conveniently into the coupling.In addition, there is a possibility of allowing, without a tool, anunforeseeable release of the corrugated pipe either by means ofunintentional and/or intentional misuse swivelling of a correspondingfinger. This is a significant disadvantage especially in safety-relevantareas and applications.

From the statements made above, the problem subsequently results that,with the help of newly designed securing couplings for corrugated pipes,the above-mentioned disadvantages are to be at least partiallyeliminated. The resulting problem is, in particular, to provide securingcouplings for corrugated pipes which—especially only with the help of atool—allow in an uncomplicated manner the possible release of apreviously fixed-positioned corrugated pipe and which prevent thecorrugated pipe from slipping out of position unintentionally.

SUMMARY OF THE INVENTION

The securing coupling according to the invention includes a tubularsleeve with an open lead-in end for receiving a corrugated pipe, atleast a first locking tongue which is movably arranged in a firstaperture in the circumferential wall of the sleeve, and at least oneblocking projection for the engagement into a circumferential groove ofthe corrugated pipe. The locking tongue, with reference to the sleeve,is connected by means of at least one securing element at the sleeve,radially movable with a spring effect, so that the blocking projectioncan be disengaged from the groove of the corrugated pipe.

The locking tongue is preferably arranged in a sleeve section which ispivotable radially outward from the peripheral wall of the tubularsleeve by means of an integral hinge.

By means of the integral hinge and with a corresponding design andconstruction of the sleeve section and the part of the tubular elementof the securing coupling accommodating the open end of the sleevesection, an uncomplicated opening is possible only with the help of atool. The blocking projection of the tongue on the sleeve section isthus disengaged from the groove of the corrugated pipe.

The securing coupling preferably also includes at least one secondlocking tongue, movably arranged in a second aperture in the peripheralwall of the sleeve, opposite the first locking tongue, where the secondlocking tongue with reference to the sleeve is joined by way of at leastone securing element not designed as an integral hinge. In this way, andwith the opening of a sleeve section, an unintentional or accidentalslipping-out of the corrugated pipe is practically avoided because atleast the second locking tongue engages in the peripheral groove of thecorrugated pipe. With the design of the connection or joining of thesecond locking tongue as an integral hinge, a release of a corrugatedpipe would only be possible by way of an unlocking with an auxiliarytool where, with a previous unlocking, an unintentional slipping-outwould be possible upon loosening/disengagement of the (first) integralhinge. In order to avoid this, the second joining/connection of thesecond locking tongue is not to be designed as an integral hinge.

The tubular sleeve includes a bearing ring at the open lead-in end, atleast in the zone of the sleeve section, as a corrugated pipe is fixedlypositioned in the securing coupling, and the stability of thejoining/connection of the sleeve section to the sleeve established byway of the integral hinge is increased.

Furthermore, the bearing ring is oval shaped because a very goodfixation of a corrugated pipe is possible and, beyond this, theloosening/disengagement of the corrugated pipe—with the sleeve sectionopened—is only possible with the help of a tool at radial displacementof the second locking tongue into a release position outside ofengagement in a groove of the corrugated pipe. Therefore, anunintentional falling-out of the corrugated pipe is practically ruledout.

With this design arrangement, and by means of a light reciprocatingmovement of the previously fixed-positioned hose and/or by minor radialdeformation of the sleeve, the corrugated pipe can be released and,consequently, drawn out of the securing coupling. This represents—afteropening the sleeve section—a particularly uncomplicated release of thecorrugated pipe from the securing coupling.

The second locking tongue includes a lever arm protruding over thesecuring element in the axial direction over the open lead-in end. Bypivoting the lever arm in the direction of the sleeve axis, andsubsequently a relatively convenient release of the secured corrugatedpipe with the integral hinge opened—is possible by means of a radialpivoting of the second locking tongue to a release position outside ofengagement.

The second securing coupling includes a tubular sleeve with an openlead-in end for accommodating the corrugated pipe, where the sleevecarries at least one blocking projection for the engagement into aperipheral grove of the corrugated pipe. The blocking projection isarranged in a radially outward pivoting sleeve section from theperipheral wall of the tubular sleeve by means of an integral hinge.

By means of the integral hinge and with a corresponding design andconstruction of the sleeve section and the part of the tubular elementof the securing coupling accommodating the open end of the sleevesection, an uncomplicated opening is possible only with the help of atool. The blocking projection of the sleeve section is disengaged fromthe groove of the corrugated pipe.

The securing coupling preferably includes at least one locking tongue,movably arranged in a recess in the peripheral wall of the sleeve,opposite the blocking projection, where the locking tongue withreference to the sleeve is joined by way of at least one securingelement not designed as an integral hinge. In this way, and when openingthe sleeve section, an unintentional/accidental slipping-out of thecorrugated pipe is practically avoided because at least the lockingtongue engages in the peripheral groove of the corrugated pipe. With thedesign of the joining/connection of the locking tongue as an integralhinge, a release of the corrugated pipe would only be possible by way ofan unlocking with an auxiliary tool, where, with a previous unlocking,an unintentional slipping-out would be possible uponloosening/disengagement of the (first) integral hinge. In order to avoidthis, the second joining/connection of the second locking tongue is notto be designed as an integral hinge.

The tubular sleeve includes a bearing ring at the open lead-in end, atleast in the zone of the sleeve section, as a corrugated pipe is fixedlypositioned in the securing coupling, and the stability of thejoining/connection of the sleeve section to the sleeve established byway of the integral hinge is increased.

Furthermore, the bearing ring is oval shaped because a very goodfixation of a corrugated pipe is possible and, beyond this, theloosening/disengagement of the corrugated pipe—with the sleeve sectionopened—is only possible with the help of a tool at radial displacementof the second locking tongue into a release position outside ofengagement in a groove of the corrugated pipe. Therefore, anunintentional falling-out of the corrugated pipe is practically ruledout.

The second locking tongue includes a lever arm protruding over thesecuring element in the axial direction over the open lead-in end. Bypivoting the lever arm in the direction of the sleeve axis, a relativelyconvenient release of the secured corrugated pipe—with the integralhinge opened—is possible by means of a radial pivoting of the secondlocking tongue to a release position outside of engagement.

The third securing coupling includes a tubular sleeve with an openlead-in end for accommodating the corrugated pipe, where the sleevecarries at least one blocking projection for the engagement into aperipheral grove of the corrugated pipe. The blocking projection isarranged in a radially outward pivoting sleeve section from theperipheral wall of the tubular sleeve by means of an integral hinge.

The blocking projection is part of a locking unit arranged between twoapertures, in particular slot-shaped apertures, and by way of twosecuring elements, for example wide material connecting, joined at theforward-tilting sleeve section. The locking unit's external and/orinternal partial tubular jacket profile has an attenuation at least inthe longitudinal direction of the sleeve section.

Based on this material attenuation, and despite the bilateral joining tothe sleeve section, a good radial pivoting capability with asimultaneous high strength level of the locking unit is established.

The securing coupling includes at least one locking tongue, movablyarranged in an aperture in the peripheral wall of the sleeve, oppositethe blocking projection, where the locking tongue with reference to thesleeve is joined by way of at least one securing element not designed asan integral hinge. In this way, and with the opening of a sleevesection, an unintentional or accidental slipping-out of the corrugatedpipe is practically avoided because at least the locking tongue engagesin the peripheral groove of the corrugated pipe. With the design of theconnection or joining of the locking tongue as an integral hinge, arelease of a corrugated pipe would only be possible by way of anunlocking with an auxiliary tool where, with a previous unlocking, anunintentional slipping-out would be possible uponloosening/disengagement of the (first) integral hinge. In order to avoidthis, the second joining/connection of the second locking tongue is notto be designed as an integral hinge.

The tubular sleeve includes a bearing ring at the open lead-in end, atleast in the zone of the sleeve section, as a corrugated pipe is fixedlypositioned in the securing coupling, and the stability of thejoining/connection of the sleeve section to the sleeve established byway of the integral hinge is increased.

Furthermore, the bearing ring is oval shaped as a very good fixation ofa corrugated pipe is possible and, beyond this, theloosening/disengagement of the corrugated pipe—with the sleeve sectionopened—is only possible with the help of a tool at radial displacementof the second locking tongue into a release position outside ofengagement in a groove of the corrugated pipe. Therefore, anunintentional falling-out of the corrugated pipe is practically ruledout.

With this design arrangement, and by means of a light reciprocatingmovement of the previously fixedly positioned hose and/or by minorradial deformation of the sleeve, the corrugated pipe can be releasedand, consequently, drawn out of the securing coupling. Thisrepresents—after opening the sleeve section—a particularly uncomplicatedpossibility of separating the corrugated pipe from the securingcoupling.

The second locking tongue includes a lever arm protruding over thesecuring element in the axial direction over the open lead-in end. Bypivoting the lever arm in the direction of the sleeve axis, a relativelyconvenient release of the secured corrugated pipe—with the integralhinge opened—is possible by means of a radial pivoting of the secondlocking tongue to a release position outside of engagement.

Where the third securing coupling is concerned, it is advantageous if atleast one securing element includes at least one further aperture, forexample a further slot in the longitudinal direction of the sleevesection, because the flexibility of the locking unit is increased inthis way.

Where the first securing coupling is concerned, it is advantageous ifthe locking tongue is conically-tapered in the direction away from theblocking projection, and/or the second locking tongue isconically-tapered in the direction away from the blocking projection,because in this way a higher degree of pivoting and, subsequently, amore convenient dismantling is possible.

Where the second securing coupling is concerned, it is advantageous ifthe locking tongue is conically-tapered in the direction away from theblocking projection, because in this way a higher degree of swivellingand, subsequently, a more convenient dismantling is possible.

Where the securing coupling is concerned, the sleeve advantageouslyincludes a slot-shaped recess, designed as a hollow profile, forreceiving a free end of the sleeve section because this designarrangement involves a possibility of a locking capability of the sleevesection in the sleeve which is relatively easy to realise and isfavourable with regard to the costs.

In this connection it is advantageous if the slot-shaped recess includesan abutting surface forming a first projection in the hollow profile ofthe recess and the free end of the sleeve section includes acorresponding abutting surface with a second projection for a reargrasping of the first projection during the locking-in action of thesleeve section in the sleeve.

It is emphasised that the back-up ring can also have a circular-shapeddesign.

The fourth securing coupling for corrugated pipes includes a tubularsleeve with an open lead-in end for accommodating the corrugated pipe aswell as at least a first locking tongue which is movably arranged in afirst aperture in the peripheral wall of the sleeve, where the sleevecarries at least one blocking projection for the engagement into aperipheral groove of the corrugated pipe. The locking tongue, withreference to the sleeve, is connected by means of at least one securingelement at the sleeve, radially movable with resilience so that theblocking projection can be brought into a release position outside ofengagement with the groove of the corrugated pipe.

The securing coupling includes at least one further locking tongue,radially and movably arranged in a further aperture recess in theperipheral wall of the sleeve where this, with reference to the sleeve,is joined by at least one further securing element. All securingelements are ligament-shaped in design, whereas all locking tongues inthe direction away from the blocking projections are conically-taperedin design.

Where the fourth securing coupling is concerned, it is advantageous whenthis includes at least three, especially four locking tongues because arelatively high engagement redundancy is ensured in this way. In theevent of a failure of any one single locking tongue, the remaininglocking tongues, as a rule, always engage and prevent an uncontrolledrelease.

When at least one locking tongue includes an oval-shaped aperture, thisrepresents material saving and, subsequently, cost savings whenmanufacturing the securing coupling.

It is an advantage for the securing coupling if at least one lockingtongue is connected with the sleeve by at least one connecting elementwhich is arch shaped in the resting position, in the radial directionand limited in pivoting movement. An excessively wide pivoting atexcessively strong material stressing is thereby avoided.

The securing coupling kit according to the invention, consists of asecuring coupling in accordance with the fourth variant and adismantling tool, where the dismantling tool during dismantling graspsaround the hose and is slidable in the longitudinal axis directionbetween the corrugated pipe and the securing coupling. The tool includestwo semi-shells which can be assembled with one another, or includes twosemi-shells which can pivot together by means of at least one connectingelement similar to a hinge.

During dismantling, the locking tongues are brought out of engagement bypushing the tool between the corrugated pipe and the securing couplingso that the corrugated pipe can be drawn out of the securing coupling.

Moreover, it is also advantageous if at least one semi-shell includes atleast one tongue having a radial pivoting movement because, after theembracing of the corrugated pipe with the dismantling tool and pushingit in between corrugated pipe and securing coupling, the tongue can bebrought into engagement, preferentially by means of a switch surfaceplaced on the outer surface of a semi-shell, with the corrugated pipeand so that the corrugated pipe can be drawn out of the securingcoupling. This method of dismantling is particularly advantageous withvery soft hoses as the mechanical loading on these is particularly low.

The securing coupling according to the invention, as well as thedismantling tool can consist of various material types and materialcompositions, for example polyethylene, polyimide etc. and beyond this,can be designed in accordance with the specific assembly requirements invarious forms with regard to the sleeve, for example in the form ofangular pieces, straight pieces with or without flanges etc.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective illustration of a first embodiment of thesecuring coupling according to the invention;

FIG. 2 is a transverse view of the securing coupling shown in FIG. 1with the opened sleeve section;

FIG. 3 is a transverse view of the securing coupling shown in FIG. 1with the closed sleeve section;

FIG. 4 is a perspective illustration of a second embodiment of thesecuring coupling according to the invention;

FIG. 5 is a perspective illustration of a third embodiment of thesecuring coupling according to the invention;

FIG. 6 is a cross-sectional view of the securing coupling shown in FIG.5 with the closed sleeve section;

FIG. 7 is a longitudinal view of a fourth embodiment of the securingcoupling according to the invention;

FIG. 8 is a longitudinal view of a fourth embodiment of the securingcoupling;

FIG. 9 is a radial transverse view of the securing coupling illustratedin FIG. 7;

FIG. 10 is a longitudinal view of a dismantling tool; and

FIG. 11 is an axial view of the dismantling tool illustrated in FIG. 10.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The securing coupling shown in FIG. 1 includes an angular and tubularsleeve 1 which has an open lead-in end for accommodating a corrugatedpipe. In addition, there is a first locking tongue 2 which is movablyarranged in a first aperture 3—at closed condition of the sleeve section7—in the peripheral wall 4 of the sleeve 1. The sleeve section 7 isjoined/hinged to the sleeve 1 by means of an integral hinge 18. Thelocking tongue 2 includes a blocking projection 5 for the engagementinto a peripheral groove of a corrugated pipe. The locking tongue 2,with reference to the sleeve 1, is connected by means of one securingelement 6, here in the form of a material connection, at the sleeve 1,radially movable with a spring effect, so that the blocking projection 5can be brought into a release position outside of engagement with thegroove of a corresponding corrugated pipe. The locking tongue 2 isarranged in a radially forward-tilting sleeve section 7 from theperipheral wall 4 of the tubular sleeve 1 by means of an integral hinge18.

In addition, the securing coupling includes a second locking tongue 8,movably arranged in a second aperture 9 in the peripheral wall 4 of thesleeve 1, opposite the first locking tongue 2, where the second lockingtongue 8, with reference to the sleeve 1, is joined by way of a securingelement 10, here in the form of a material connection.

The tubular sleeve 1 includes a circular-shaped bearing ring 19 at theopen lead-in end.

The securing coupling shown in FIG. 4 includes an angular and tubularsleeve 1 which has an open lead-in end for accommodating a corrugatedpipe. In addition, there are three (one is not visible) blockingprojections 5, 5′ which—with the closed condition of a sleeve section7—are rigidly arranged in the peripheral wall 4 of the sleeve 1.

The sleeve section 7 is joined to the sleeve 1 by means of an integralhinge 18. The blocking projections 5,5′ are arranged radially andforward-tilting in sleeve section 7, from the peripheral wall 4 of thetubular sleeve 1 by means of an integral hinge 18. In addition, thesecuring coupling includes a locking tongue 8, opposite the -blockingprojections 5,5′, movably arranged in a recess 9 in the peripheral wall4 of the sleeve 1, where the locking tongue 8, with reference to thesleeve 1, is joined by means of a securing element 10, here in the formof a material connection. The tubular sleeve 1 includes acircular-shaped bearing ring 19 at the open lead-in end.

These features in the following description of the invention-relatedfirst securing coupling are clearly recognisable in the FIGS. 2 and 3,whereas for the second securing.

The slot-shaped recess 13 includes an abutting surface 15 forming afirst projection 14 in the hollow profile of the recess 13 and the freeend of the sleeve section 7 includes a corresponding abutting surface 16with a second projection 17 to establish a rear grasp of the firstprojection 14 when the sleeve section 7 locks into the sleeve 1 (seeFIG. 2).

In FIG. 3 it can be finally seen that, in the closed condition of sleevesection 7, the second projection 17 has a rear grasp on the firstprojection 14 and thus accomplishing a locking status. This lockingstatus can only be loosened by means of a pin, inserted into the recess13 so that a relative movement of the two projections 14, 17 away fromone another takes place, and at the same time the sleeve section 7 istilted out radially from the peripheral wall 4 of the tubular sleeve 1.In this position, the corresponding corrugated pipe is held only by theblocking projection 11 of the second locking tongue 8. By activating thelever arm 12, the corrugated pipe is finally released.

The securing coupling shown in FIG. 5 includes an angular and tubularsleeve 1 which has an open lead-in end for accommodating a corrugatedpipe. In addition, there is one blocking projection 5, which with theclosed condition of a sleeve section 7—is rigidly arranged in theperipheral wall 4 of the sleeve 1. The sleeve section 7 is joined/hingedto the sleeve 1 by means of an integral hinge 18. The blockingprojection 5, is arranged radially and forward-tilting in sleeve section7, from the peripheral wall 4 of the tubular sleeve 1 by means of anintegral hinge 18. The blocking projection 5 is part of a locking unit 2a, arranged between two apertures 3 a and joined by way of two securingelements 6 a in the form of wide material connections at theforward-tilting sleeve section 7. The locking unit's external parttubular jacket profile 20 includes an attenuation (not visible) in thelongitudinal direction of the sleeve section 7. Both materialconnections are attenuated by means of further slot-shaped apertures 3b.

The securing coupling includes a locking tongue 8, movably arranged inan aperture 9 in the peripheral wall 4 of the sleeve 1, oppositeblocking projection 5, where the locking tongue 8 with reference to thesleeve 1 is joined by means of a securing element 10, here in the formof a material connection.

The tubular sleeve I indicates a circular-shaped bearing ring 19 at theopen lead-in end.

The release position of the blocking projection 11 is facilitated by thefact that the locking tongue 8 has a lever arm 12 protruding over thesecuring element 10 in the axial direction over the open lead-in end.

Furthermore, the sleeve 1 has a slot-shaped recess 13, designed as ahollow profile, for accommodating the sleeve section 7.

In FIG. 6, by comparison with FIG. 3, the part tubular (here: runningover the length of the sleeve section 7) jacket profile 20 of thelocking unit 2 a can be seen. In the cross-sectional view, this is seenas relatively thin, and the reason for this is that the correspondingmaterial attenuation runs over the entire length.

In FIGS. 7 and 8 the locking tongues 2,B are joined with sleeve 1 bysecuring elements 6, 10 in apertures 3,9, designed as a connection ineach case, radially and with resilience. In the design as shown in FIG.8, the locking tongues 2 include, in each case, two oval apertures 21.In FIG. 9 there are four blocking projections Sa, 5 a′, 5 a″, 5 a″, inthe radial transverse view for the engagement into a peripheral groove(corrugate trough) of the corrugated pipe. In FIG. 8 arch shapedconnecting elements 22 can be seen in rest position, designed forpreventing excessive radial pivoting.

In FIG. 10 a longitudinal view and in FIG. 11 an end view of adevelopment of a dismantling tool are shown. The dismantling toolcomprises two semi-shells 23, joined together by means of threehinge-like connecting elements 24, where one semi-shell 23 includes aresilient tongue 25 which is brought into engagement with a corrugatetrough of a corrugated pipe by means of switch surface 26 placed on theouter surface of a semi-shell 23, and by means of light pressing action.

What is claimed is:
 1. A securing coupling for a corrugated pipe havinga circumferential groove, said securing coupling comprising a tubularsleeve having a circumferential wall and an open end for receiving thecorrugated pipe, said tubular sleeve comprising a sleeve section whichis pivotable radially outward from said sleeve by means of an integralhinge connecting said sleeve section to said circumferential wall, afirst locking tongue arranged in a first aperture in saidcircumferential wall, said first aperture being located in said sleevesection, said first locking tongue being resiliently connected to saidsleeve section and having a first blocking projection which isengageable with said circumferential groove in said pipe, said firstlocking tongue being movable radially outward with resilience to releasesaid blocking projection from said groove, and a second locking tonguearranged in a second aperture in said circumferential wall, said secondaperture being located opposite from said first aperture, said secondlocking tongue being resiliently connected to said sleeve and having asecond blocking projection which is engageable with said circumferentialgroove in said pipe, said second locking tongue having a lever arm whichextends toward said open end of said sleeve oppositely from saidblocking projection, said lever arm being movable radially inward tocause said second blocking projection to move radially outward withresilience to release said second blocking projection from said groove.2. A securing coupling as in claim 1 wherein at least one of said firstand second locking tongues is tapered so that it becomes narrower in adirection away from said blocking projection.
 3. A securing coupling fora corrugated pipe having a circumferential groove, said securingcoupling comprising a tubular sleeve having a circumferential wall andan open end for receiving the corrugated pipe, said tubular sleevecomprising a sleeve section which is pivotable radially outward fromsaid sleeve by means of an integral hinge connecting said sleeve sectionto said circumferential wall, a locking unit arranged on said sleevesection, said locking unit comprising a first blocking projection whichis engageable with said circumferential groove in said pipe, and alocking tongue arranged in an aperture in said circumferential wall,said aperture being located opposite from said first blockingprojection, said locking tongue being resiliently connected to saidsleeve and having a second blocking projection which is engageable withsaid circumferential groove in said pipe, said locking tongue having alever arm which extends toward said open end of said sleeve oppositelyfrom said blocking projection, said lever arm being movable radiallyinward to cause said blocking projection to move radially outward withresilience to release said second blocking projection from said groove.4. A securing coupling as in claim 3 wherein said locking unit isarranged between two apertures in said sleeve section, said locking unitfurther comprising two securing elements which connect said firstblocking projection to said sleeve section to limit radial movement ofsaid blocking section.
 5. A securing coupling as in claim 4 wherein atleast one of said securing elements comprises an additional aperture. 6.A securing coupling as in claim 3 wherein said locking tongue is taperedso that it becomes narrower in a direction away from said blockingprojection.
 7. A securing coupling as in claim 3 wherein said sleevesection has a free end opposite from said hinge, said sleeve comprisinga slot shaped recess which receives said free end.
 8. A securingcoupling as in claim 7 wherein said slot shaped recess comprises anabutting surface forming a first projection in said recess, said freeend of said sleeve section comprising an abutting surface forming asecond projection which engages said first projection to lock said freeend in said recess.
 9. A securing coupling for a corrugated pipe havinga circumferential groove, said securing coupling comprising a tubularsleeve having a circumferential wall and an open end for receiving thecorrugated pipe, at least two locking tongues arranged in respectiveapertures in said circumferential wall, each said locking tongue beingresiliently connected to said circumferential wall and having a blockingprojection which is engageable with said circumferential groove in saidpipe, each said locking tongue being movable radially outward withresilience to release said blocking projection from said groove, eachsaid locking tongue tapering so that it becomes narrower in a directionaway from the respective said blocking projection wherein at least oneof said locking tongues is connected to said circumferential wall by anarched connecting element which limits movement of said tongue in aradial direction.
 10. A securing coupling as in claim 9 comprising threesaid locking tongues.
 11. A securing coupling as in claim 9 comprisingfour said locking tongues.
 12. A securing coupling as in claim 9 whereinat least one of said locking tongues has at least one aperture.
 13. Asecuring coupling kit comprising a securing coupling for a corrugatedpipe having a circumferential groove, said securing coupling comprisinga tubular sleeve having a circumferential wall and an open end forreceiving the corrugated pipe, and at least two locking tongues arrangedin respective apertures in said circumferential wall, each said lockingtongue being resiliently connected to said circumferential wall andhaving a blocking projection which is engageable with saidcircumferential groove in said pipe, each said locking tongue beingmovable radially outward with resilience to release said blockingprojection from said groove, each said locking tongue tapering so thatit becomes narrower in a direction away from the respective saidblocking projection, and a dismantling tool which fits around the pipeand is slidable axially between the corrugated pipe and the securingcoupling, said dismantling tool comprising two semi-shells which fittogether to form a tubular tool assembly, at least one of saidsemi-shells comprising at least one locking tongue which can pivotradially inward to engage the corrugated pipe so that the corrugatedpipe can be drawn out of the securing coupling.
 14. A securing couplingkit as in claim 13 wherein said two semi-shells are connected by atleast one hinge which permits said semi-shells to pivot together to formsaid tubular tool assembly.